package videoeditor.bhuvnesh.com.ffmpegvideoeditor.views;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.view.View;

public class VisualizerView extends View {

 private byte[] mBytes;
 private float[] mPoints;
 private Rect mRect = new Rect();
 private Paint mForePaint = new Paint();

 public VisualizerView(Context context) {
  super(context);
  init();
 }

 public VisualizerView(Context context, AttributeSet attrs) {
  super(context, attrs);
  init();
 }

 public VisualizerView(Context context, AttributeSet attrs, int defStyleAttr) {
  super(context, attrs, defStyleAttr);
  init();
 }

 private void init() {
  mBytes = null;
  mForePaint.setStrokeWidth(1f);
  mForePaint.setAntiAlias(true);
  mForePaint.setColor(Color.rgb(0, 128, 255));
 }

 public void updateVisualizer(byte[] bytes) {
  mBytes = bytes;
  invalidate();
 }

 @Override
 protected void onDraw(Canvas canvas) {
  super.onDraw(canvas);
  if (mBytes == null) {
   return;
  }
  if (mPoints == null || mPoints.length < mBytes.length * 4) {
   mPoints = new float[mBytes.length * 4];
  }
  mRect.set(0, 0, getWidth(), getHeight());
  for (int i = 0; i < mBytes.length - 1; i++) {
   mPoints[i * 4] = mRect.width() * i / (mBytes.length - 1);
   mPoints[i * 4 + 1] = mRect.height() / 2
     + ((byte) (mBytes[i] + 128)) * (mRect.height() / 2) / 128;
   mPoints[i * 4 + 2] = mRect.width() * (i + 1) / (mBytes.length - 1);
   mPoints[i * 4 + 3] = mRect.height() / 2
     + ((byte) (mBytes[i + 1] + 128)) * (mRect.height() / 2)
     / 128;
  }
  canvas.drawLines(mPoints, mForePaint);
 }

}